System and method for two sided sheet treating

ABSTRACT

A system and a method for coating two sides of a laminate material is disclosed in which one side of the laminate material is coated with one substance and the second side is coated with a different substance. The method described is particularly suited for applying a substance providing balancing characteristics desirable in the end product to one side of the laminate material and applying a substance providing other characteristics desirable in the end product to the other side of the laminate material. For example, a balancing substance may be applied on one side of a kraft paper sheet and a substance providing structural bonding applied to the other side, thereby eliminating the need to use a discrete balancing sheet in a laminate. The kraft sheet thus coated may be used to form a laminate panel.

CROSS-REFERENCE TO RELATED APPLICATIONS

[0001] The present application is a Divisional of co-pending andcommonly assigned U.S. patent application Ser. No. 09/267,493, filedMar. 12, 1999, entitled “SYSTEM AND METHOD FOR TWO SIDED SHEETTREATING”. The present application is also related to now abandoned andcommonly assigned U.S. patent application Ser. No. 09/267,180, co-filedMar. 12, 1999, also entitled “SYSTEM AND METHOD FOR TWO SIDED SHEETTREATING”, the disclosures of which are incorporated herein byreference.

TECHNICAL FIELD

[0002] The present invention relates generally to the manufacture oflaminated products such as may be used for decorative flooring, counterand table tops, and wall panels, and more specifically to systems andmethods for manufacturing such products by applying a coating of thesame or different materials on opposing sides of a laminate material.

BACKGROUND OF THE INVENTION

[0003] The ability to replicate natural materials has substantiallyimproved over the years. For example, decorative laminates have replacednatural materials in the construction of furniture, cabinets, countertops, flooring panels and other surfaces. In each of these applications,a decorative surface may be applied to a core layer or substrate,namely, plywood, particle board, chipboard, medium density fiberboard,etc. Often, a backing layer is secured to the opposite surface of thesubstrate to balance the laminates or provide other benefits.

[0004] Generally, the decorative surface and the backer layer willinclude one or more kraft paper layers which are adhesively laminatedtogether using various materials, such as melamine formaldehyde andphenolic resins. As shown in FIG. 1, a high pressure laminate 11 maycomprise a very thin overlay sheet 12 impregnated with melamine resin, adecorative sheet 13 disposed thereunder, and sheets 14 and 15 of kraftpaper impregnated with phenolic resin disposed below the decorativesheet.

[0005] The melamine impregnated overlay sheet 12 forms a hardened layeron the surface of the decorative sheet. This hardened layer of thedecorative laminate is used to protect the surface of laminate 11, suchas by making the laminate scratch and abrasion resistant. The melamineimpregnated overlay also prevents discoloration or deformity of thelaminate surface due to various external factors, such as high pressureand temperature and other ordinary stresses which occur in theenvironment where such laminates are typically used. Furthermore, theoverlay sheet is also capable of easily withstanding the thermal orchemical strains occurring in these environments. For example, themelamine overlay sheet protects the laminate from discoloring when avery hot substance, such as tea or coffee, or a very cold substance,such as ice, spills on the surface of such a laminate. Thus, themelamine coating can withstand the very high and very low temperaturesto which the laminate is exposed in everyday use.

[0006] However, the overlay sheet 12 itself may cause warping of thelaminate panel under extreme hot, cold, or dry conditions. Theconventional substrate or core layer 16 may not be able to withstand thepressure created by the movement of the melamine overlay of thedecorative surface under these extreme conditions and may deform,delaminate, or in extreme cases, break due to the pressure exerted bythe melamine overlay layer 12. Therefore, backer type laminates may beused for many applications, such as to provide balancing sheets on thebottom of decorative laminates. These backer laminates may comprise adiscrete melamine impregnated balancing layer 19 to balance the melaminelayer of the decorative surface, and sheets of phenolic resinimpregnated kraft paper 17 and 18 to correspond to the layers in thedecorative laminate. The balancing layer 19 used in prior art systems issimilar to the overlay sheet 12 of the decorative surface and uses thesame material as the overlay sheet. However, the balancing layer 19 mayor may not be transparent as it is usually not visible. The discretemelamine impregnated balancing layer 19 when used in a backer laminateprevents warping of the laminate due to the movement of the melaminelayer 12 of the decorative surface under extreme conditions.

[0007] Typically, in prior art systems, sheets of kraft paper areimpregnated with phenolic resin by submerging them in a vat which isfilled with phenolic resin and then curing the phenolic resinimpregnated kraft paper. The kraft paper soaks up a desired amount ofphenolic resin based on the time it is left in the vat and the level ofsubmergence. This method of impregnating the kraft paper is generallynot cost effective as it requires large vats providing substantial resinpool surface areas in order to allow the proper immersion of a portionof a continuous roll of kraft paper. These large pool surface areasresult in wasteful use of phenolic resin as the large vat surface areais prone to collection of contaminants and to the escaping of resinvapors thus causing variations in the percentage of solids and/or othercontrolled attributes of the resin requiring substantial portions of theresin to be disposed of from time to time. Moreover, when the resinimpregnated kraft paper is being manufactured using such vats, fumes arecreated during the process which are harmful to the workers in thevicinity of the manufacturing process. All of this is compounded by thefact that such vats of phenolic resin, or other resins, are difficult toclean requiring an inordinate amount of time to properly clean the vatsthat have been used for impregnating the kraft sheets with phenolicresin.

[0008] The melamine impregnated sheet used in the decorative and backerlayers is usually not a kraft paper sheet but rather a very thin sheetspecifically adapted, such as by controlling strand orientation,density, and porosity to carry the melamine resin. Kraft paper sheetsare typically not suitable to act as a carrier for melamine because theporosity, strand orientation, and density of kraft paper sheets are notadapted for this purpose although they are well suited for phenolicresin impregnation. Typically, a suitable sheet is impregnated withmelamine by coating both sides of the sheet with melamine formaldehyderesin and then removing excess resin from the sheet. The melamineformaldehyde coated sheet is cured under controlled conditions toproduce the melamine impregnated sheet which may be used both indecorative and backer laminates.

[0009] The laminates which are manufactured by using the phenolic resinimpregnated kraft paper sheets and the melamine impregnated sheets asdescribed above are made by a bulky manufacturing press which isexpensive to operate. Thus, it is not cost effective or desirable to usethe press to produce individual laminates. Therefore, in the typicalmanufacturing process a plurality of laminates are produced from eachpress during each press cycle to make the most efficient use of thepress.

[0010] Typically, in such a press system pairs of laminate assemblies,similar to the laminate assembly shown in FIG. 1, with or withoutpattern layer 13, are positioned back-to-back with the phenolic resinimpregnated kraft paper sheet 15 of one laminate assembly facing thephenolic resin impregnated kraft paper sheet of a second laminateassembly with a discrete release sheet disposed there between asdescribed below. These pairs of laminate assemblies are separated fromother laminate assembly pairs by metal sheets or press plates. Usuallyduring the manufacturing process each laminate assembly 11 also includesa sheet, known as release sheet. The release sheet is usually kraftpaper which has been coated with a release agent on at least one side.This release sheet is placed at the end of each laminate assemblyadjacent to the phenolic resin impregnated kraft paper layer 15 awayfrom the press plates to provide a release mechanism between the pairedlaminate assemblies. The release sheet facilitates easy separation ofthe laminate assemblies after pressing as the release agent will notallow cross linking of the laminate assemblies at least with respect tothe side of the laminate assembly to which the release sheet is applied.

[0011] Typically these laminate assemblies are subjected to a pressureand temperature for a time sufficiently long enough to cure thelaminating resins impregnating the respective layers. The hightemperatures and pressure cause the resins within the sheets to flowwhich consolidates the whole into an integral mass. Thus, typically thediscrete melamine layer sticks to the phenolic resin impregnated kraftpaper layer disposed adjacent to it due to the migration of the phenolicresin into at least a portion of the discrete melamine layer to providestructural cross linking. Accordingly, the melamine sheet generally addsto the thickness or bulk of the laminate.

[0012] The conventional laminates produced by the above described priorart systems may then be cut to size and employed in a variety ofapplications such as decorative surfaces for desktops, tabletops, wallpanels, and the like such as by bonding them to a core layer orsubstrate with a conventional adhesive such as contact cement. Theselaminates may also be used as backer layers common in laminated flooringproducts.

[0013] When such a laminate is used as a decorative laminate, themelamine layer in the laminate may be used to protect the surface of thedecorative laminate. As mentioned above, however, such a use of amelamine layer on a decorative side of a laminate may necessitate theuse of a melamine layer on a backer to provide balancing. When such alaminate is used as a backer laminate, the melamine impregnated sheetacts mostly as a carrier for melamine in order to provide a melaminelayer to counteract the stress created by the melamine sheet of thedecorative laminate to prevent warping of the laminate.

[0014] The use of a discrete melamine sheet during pressing of laminateassemblies as described above presents certain disadvantages. Themelamine sheet itself contributes substantially to the material cost ofthe manufactured laminate as the melamine sheet is generally moreexpensive than the kraft paper sheets. As discussed above, kraft paperis not a good carrier of melamine. Thus, a different kind of thin sheetis usually adapted to provide the necessary strand orientation, density,and porosity, to enable it to act as a carrier for melamine. Thisrequires a complete additional processing step to provide a discretesheet coated with melamine. Also, as the melamine sheet of prior artsystems is very thin, it may easily be damaged during handling,resulting in substantial losses due to handling spoilage. Furthermore,as the melamine sheet is an additional sheet that has to be processed,there are substantial processing costs, such as handling and collatingcosts, scrap losses due to the brittle and difficult to handle nature ofthe melamine impregnated sheet, in addition to the costs associated withimpregnating the sheet itself with melamine. Furthermore, thetranslucent character of the overlay sheet, although present due to thesame type sheet being used for providing a decorative overlay being usedfor backer purposes, is not generally necessary for backer laminates.

[0015] Moreover, in order to achieve the desired thickness of thelaminate assembly and still allow the use of a discrete melamine sheet,more sheets of thinner material instead of fewer sheets of thickermaterial have to be used. This increases the manufacturing overhead as agreater number of sheets have to be handled and processed before theycan be used in the laminate assembly. Such handling and processing mayinclude impregnating the sheets with phenolic resin, cutting the sheetsto the desired size, and collating the sheets for subsequent pressing.

[0016] Furthermore, since the overlay sheet becomes part of the laminateafter pressing, at least one sheet of the laminate does not includephenolic resin saturation to provide structural bonding, but ratherrelies on migration of the resin from an adjoining sheet. Thus, priorart systems do not provide consistent structural bonding between thedifferent layers of the laminate as the phenolic resin saturation of atleast one layer is less than the other layers. Therefore, the structuralbond between different layers of the laminate assembly are not the sameand may result in earlier delamination of a layer of the laminate.

[0017] It should be clear that the use of the melamine impregnated sheetcontributes substantially to the cost of the manufactured laminate andalso adds to the product cycle time. Not only are there raw materialcosts involved with the use of a separate melamine sheet, but alsosubstantial undesirable processing costs are inherent with such a use.

[0018] Thus, there is a need in the art for a system and method ofmanufacturing laminates using the advantages offered by melamineimpregnated sheets as a discrete sheet in laminates without introducingunnecessary costs, handling steps, or structural disadvantages attendantwith the use of prior art discrete melamine sheets.

BRIEF SUMMARY OF THE INVENTION

[0019] The present invention is directed to a system and method forcoating different surfaces of laminate material, such as a sheet ofkraft paper, with materials having desired characteristics.

[0020] Accordingly, in various embodiments of the present invention, oneside of a sheet, such as a kraft paper or other laminate material usedin constructing a laminated product, is coated with a substanceproviding first desired characteristics. For example, it may bedesirable that a backer layer of a laminated product contain a laminatematerial impregnated or coated with a substance to balance or counteractthe pressure created by a layer of the decorative side that has beenimpregnated or coated with the same substance to protect the laminatedproduct from strains associated with everyday use of such products. Suchstrains may include scratches, nicks, marks and other stresses that arepresent in the environment where the laminate is typically used.Therefore, in a various embodiments of the present invention, a laminatematerial, such as kraft paper, used in such a backer layer, is coated orimpregnated with such a substance to provide the desired characteristicsto the laminate. For example, melamine may be used to coat one side ofthe kraft paper, to provide the desired balancing (and/or protective)characteristics to the kraft paper. Moreover, certain acrylics andpolyesters may also be used to provide the desired balancing (and/orprotective) characteristics.

[0021] According to this embodiment of the invention, another side ofthe kraft paper is coated with a substance providing secondcharacteristics desirable in the end product. For example, withlaminates it may be desirable to coat an opposing side of the kraftpaper with phenolic resin in order to provide desired mechanical bondingwith additional layers of kraft paper or other laminate material.

[0022] Although described above with respect to the use of melamine asproviding a desired balancing (and/or protective) characteristic, itshould be appreciated that any substance providing desiredcharacteristics may be used without departing from the spirit of thepresent invention. Likewise there is no limitation to the use ofphenolic resin on a second side of the laminate material and anymaterial providing characteristics desirable in the end product may beused. Also, if desired, the second side of the sheet may be leftuncoated.

[0023] Preferably, reverse roll coating in which a roll of paper isunwound and passed over a series of rollers such that one side of thepaper is treated with a substance providing first desiredcharacteristics and the other side is treated with a substance providingsecond desired characteristics, is used to provide precisely controlledapplication of desired substances to the laminate material. However,although reverse roll coating is used in a various embodiments, anyprocess suitable for precisely treating different surfaces of a laminatematerial may be used according to the present invention.

[0024] The present invention provides advantages not available in theprior art. For example, the laminate material so treated serves thefunction of a balancing sheet in a laminate assembly, eliminating theneed for a separate melamine sheet such as in the backer layer of alaminate. Also, if desired the laminate material may be used in adecorative laminate to provide desired protective characteristics to thelaminate. This sheet of laminate material may then be laminated withother laminate material sheets to manufacture a laminate of the desiredthickness and having the desired characteristics. Thus, the overheadassociated with the raw material costs, handling, and coating of thediscrete melamine impregnated sheets of the prior art is eliminatedwhile providing desired attributes in the laminated assembly. Forexample, the various embodiments wherein phenolic resin is provided on aside of this sheet results in a final sheet in the laminate assemblyhave structural attributes consistent with those of the other laminatematerials of the laminate assembly, due to this sheet utilized forproviding the balancing (and/or protective) functionality also havingthe phenolic resin.

[0025] Moreover, the kraft paper sheet, which is coated on both sideswith different or same substances according to the various embodimentsof the present invention, itself is less expensive than the balancing(and/or protective) sheet used in prior art systems. Also, other thickersheets of kraft paper may be used instead of the thinner sheets of kraftpaper used in prior art systems because there is no need to account forthe thickness of the balancing sheet in the manufacture of the laminate.These thicker sheets, including the less expensive coated sheet of thevarious embodiments of the present invention, are easier to handle thanthe thinner sheets, and are less easily torn, thus reducing wastage dueto scrap during handling. Furthermore, fewer sheets are now required tobe cut to the desired size and there is less handling and lay up costsat the laminate manufacturing plant.

[0026] The present invention also provides more control of the finalthickness of the laminate since the thickness of the laminate materialsused may now be selected without concern for the thickness of abalancing sheet which must be accounted for in the total thickness ofthe laminate assembly but which cannot be relied upon for providing themechanical integrity of the sheets treated to provide the abovementioned cross linking.

[0027] Therefore, it is an object of the present invention to provide asystem and method for coating a sheet with different materials ondifferent surfaces of the sheet.

[0028] It is another object of the present invention to coat one surfaceof a sheet with a material to provide first desirable characteristicsand at the same time to reduce the manufacturing steps required for anend product and/or the cost of the end product. It is a related objectof the present invention to coat another surface of the sheet with adifferent or similar substance to provide second characteristics thatare desirable in the end product.

[0029] It is a further object of the present invention to coat onesurface of a sheet with a material to provide desirable balancing and/orprotective characteristics and at the same time to reduce themanufacturing steps required for an end product and/or the cost of theend product.

[0030] It is a further object of the present invention to provide asingle sheet with first characteristics and second characteristicsdesirable in the end product thereby providing both benefits in a singlesheet and at the same time reducing costs associated with wastage andhandling of the sheets.

[0031] It is a still further object of the present invention to providea system and method for two sided coating a kraft paper such that oneside is coated with a balancing agent and the other side is coated witha bonding agent thereby eliminating the need to use balancing sheets ina laminate to provide a more cost efficient manufacturing process.

[0032] It is a still further object of the present invention to reducethe cost of producing laminates and also to reduce the production cycleby eliminating steps from the manufacturing process of the prior art.

[0033] It is a still further object of the present invention to providea method and system of producing laminates without the need to usediscrete balancing sheets.

[0034] The foregoing has outlined rather broadly the features andtechnical advantages of the present invention in order that the detaileddescription of the invention that follows may be better understood.Additional features and advantages of the invention will be describedhereinafter which form the subject of the claims of the invention. Itshould be appreciated by those skilled in the art that the conceptionand specific embodiment disclosed may be readily utilized as a basis formodifying or designing other structures for carrying out the samepurposes of the present invention. It should also be realized by thoseskilled in the art that such equivalent constructions do not depart fromthe spirit and scope of the invention as set forth in the appendedclaims. The novel features which are believed to be characteristic ofthe invention, both as to its organization and method of operation,together with further objects and advantages will be better understoodfrom the following description when considered in connection with theaccompanying figures. It is to be expressly understood, however, thateach of the figures is provided for the purpose of illustration anddescription only and is not intended as a definition of the limits ofthe present invention.

BRIEF DESCRIPTION OF THE DRAWINGS

[0035] For a more complete understanding of the present invention,reference is now made to the following descriptions taken in conjunctionwith the accompanying drawing, in which:

[0036]FIG. 1 shows a schematic of a laminate assembly with the differentlayers of laminate material;

[0037]FIG. 2 shows a system for reverse roll coating a sheet with twosubstances on different surfaces of the sheet;

[0038]FIG. 3 shows a schematic of a sheet that has been coated on bothsides according to the present invention;

[0039]FIG. 4 shows a schematic of an embodiment of a metering deviceadapted for use according to the present invention;

[0040]FIG. 5 is a table comparing the results of experimental testingperformed on the sheet of FIG. 3 with a prior art laminate material; and

[0041]FIGS. 6A and 6B are graphical representations of the results ofthe table of FIG. 5.

DETAILED DESCRIPTION OF THE INVENTION

[0042]FIG. 2 shows an embodiment of system 20 for applying substances toopposing surfaces of a sheet S. The system comprises, a sheet S in theform of a roll 201, a series of rollers 202, 203, 204, 205, 206, 207,208, 209, and 217, two pans 210, 213, metering devices 212, 216 and acuring device 215 such as may be an oven for applying a controlledamount of heat for subsequent curing of a coating substance. Pans 210and 213 contain substances 211 and 214, respectively. Substances 211 and214 may be the same substance or they may be different substances thatare applied on different surfaces of sheet S. Metering devices 212 and216 control the amount of substance 211 and substance 214, respectively,remaining on sheet S.

[0043] Sheet S is unwound and passed along rollers 202, 203, 204, 205,206, 207, 208, 209 and 217 to curing device 215. Rollers 207 and 209 arecoating rollers adapted to rotate within pans 210 and 213. Coatingroller 207 which is adapted to be partly or totally submerged insubstance 211 contained in pan 210 may be used to coat one side of sheetS. Similarly, coating roller 209, which may be adapted to be partly ortotally submerged in substance 214 contained in pan 213, may be used tocoat the other side of sheet S. Rollers 202, 203, 204, 205, 206 maintaina uniform tension on the surface of sheet S and prevent it from slackingand/or tearing. The tension on sheet S may be varied by adjusting thespeed of the rollers and/or the pressure exerted thereon by idlerrollers 202, 203, 204, 205, and/or 206. Although a series of rollers202, 203, 204, 205, 206, 207, 208, 209 and 217 are shown in theillustrated system embodiment, the operation of the present inventiondoes not require that all these rollers be used. For example, onlyselect ones of these rollers may be provided depending on the desiredtension and pressure to be applied on sheet S.

[0044] Substance 211 is fed into pan 210 by means of a pump (not shown).The level of substance 211 in pan 210 may be controlled by the pump suchthat the pump automatically feeds more substance 211 to pan 210 wheneversubstance 211 falls below a certain level. Roller 207 may be submergedin substance 211 up to a desired level depending on the amount ofsubstance 211 needed to coat one side of sheet S. Moreover, the desiredamount of substance 211 to be coated on one side of sheet S may also becontrolled by the pump. Thus, when coating roller 207 rotates in pan210, the surface of roller 207 is coated with substance 211 and when thefirst surface of sheet S comes in contact with roller 207, roller 207coats the first surface of sheet S with the desired amount of substance211. Moreover, by controlling the speed of the rollers the amount oftime that different parts of sheet S remain in contact with roller 207may be controlled, thus, further controlling the amount of substance 211that is applied to different parts of sheet S. Similarly, byincreasing/decreasing the pressure at which sheet S engages roller 207,the amount of substance 211 that is applied may be varied. This pressuremay be adjusted, for example, by adjustment to the aforementionedtension of sheet S.

[0045] Furthermore, as shown in FIG. 2, sheet S passes between coatingroller 207 and roller 217 such that one surface of sheet S is in contactwith roller 207 and the other surface is in contact with roller 217.Roller 217 may be used to apply pressure on sheet S, to ensure thatsheet S touches coating roller 207. Since the position of roller 217 ispreferably adjustable it may be used to control the amount of substance211 to be coated on sheet S. Roller 217 may also be used to applypressure on sheet S such that substance 217 penetrates sheet S up to adesired level. Also, if desired, the position of roller 217 may beadjusted such that it does not apply any pressure on sheet S and thussheet S may totally bypass substance 211. That is, by adjusting theposition of roller 217, one surface of sheet S may be left uncoated.

[0046] Although sheet S is described in various embodiments as cominginto contact with roller 207, it should be appreciated that operation ofthe present invention does not require such contact. For example, roller207 may be adapted to transfer coating material without contact to sheetS, such as through the use of rotational speeds sufficient to ejectcoating material onto the surface of sheet S. Additionally oralternatively, non-roller coating techniques may be used, such as theuse of spray nozzles, brush bristles, or the like.

[0047] In the illustrated embodiment, sheet S passes around roller 208which is positioned after roller 207 and changes the orientation ofsheet S such that the second side of sheet S touches coating roller 209.Metering device 212 preferably located near roller 208 in order to takeadvantage of the disposition of the surface of sheet S provided thereby,may be used to further control the amount of substance 211 remaining onsheet S. Thus, once sheet S has been coated on one side, the amount ofsubstance 211 remaining on sheet S may be further and preciselycontrolled to maintain a desired amount of the substance on the surfaceof sheet S. Thus, if desired, metering device 212 may be adjusted, suchas by being moved towards roller 208, thereby reducing the amount ofsubstance 211 remaining on sheet S. The excess of substance 211 that isremoved from sheet S is preferably caught in pan 210. On the other hand,if desired, the amount of substance 211 remaining on sheet S may beincreased by adjusting metering device 212, such as by increasing thedistance of metering device 212 from roller 208. Furthermore, meteringdevice 212 may be used to achieve a desired penetration of substance 211into sheet S, such as by adjusting device 212 to apply pressure to thesheet surface.

[0048] According to the illustrated embodiment, sheet S is made to passover coating roller 209 such that the second surface of sheet S touchescoating roller 209. Coating roller 209 is located such that, if desired,it may be submerged partially or totally in substance 214 contained inpan 213. Substance 214 is fed into pan 213 by means of a pump (notshown). The level of substance 214 in pan 213 may be controlled by thepump, such that when coating roller 209 rotates in pan 213, the surfaceof roller 209 is coated with a desired amount of substance 214. Thus,when the second surface of sheet S comes in contact with roller 209,roller 209 coats the second surface of sheet S. Moreover, by varying thespeed of the rollers the amount of time that a particular portion ofsheet S remains in contact with roller 209 may be controlled, thus,controlling the amount of substance 214 that is applied to sheet S. Aswith roller 207 described above, there is no limitation to the use ofcontact between roller 209 and sheet S in coating the second surface ofsheet S. Additionally, also as described above with respect to roller207, non-roller techniques may be utilized to coat the second surface ofsheet S.

[0049] A second metering device 216 is preferably provided in closeproximity to coating roller 209 to precisely control the amount ofsubstance 214 remaining on the second side of sheet S. Therefore, ifdesired, sheet S may be passed over metering device 216 such that thesecond surface of sheet S touches metering device 216. Although shown inthe embodiment of FIG. 2 as a different embodiment than metering device212, metering device 212 and 216 may be similar mechanisms, if desired.Additionally, metering device 216 may be disposed near a reverse roller,as is metering device 212, disposed after roller 208 and/or meteringdevice 216 may be disposed at a location other than near a reverseroller, if desired.

[0050] Sheet S is then preferably subjected to a B-curing process orother conditioning step to preferably condition substances 211 and 214,such as by drying or curing. For this purpose, sheet S may be passedthrough a conditioner 215. The environment inside conditioner 215 may becontrolled such that, if desired, different temperatures, pressures,catalysts, or the like may be maintained on opposite sides of sheet S orat different points within conditioner 215, to facilitate efficientcuring of substances 211 and 214. Since substances 211 and 214 may bedifferent substances, it is desirable to control the environment insideconditioner 215 such that substance 211 and substance 214 are curedbased on their respective desired characteristics. For this purpose,different heating elements, for example, may be provided in differentparts of conditioner 215 such that one part of conditioner 215 is moresuitable for curing substance 211 and another part of conditioner 215 ismore suitable for curing substance 214. For example, when a water basedresin, such as melamine, is used as substance 211, it may be desirableto keep a portion of the coated melamine on the surface of sheet S andthus it may be desirable to cure melamine more rapidly such as byexposing the melamine to a higher temperature initially. Accordingly,different heating elements may be provided on different sides of sheet Sto heat the two surfaces differently. For example, a cooling surface maybe provided on the first side and a heating surface may be provided onthe second side.

[0051] Furthermore, if desired an optimum temperature or otherconditioning attribute, which when applied in combination with theprecisely controlled application of each coating material according tothe present invention, may be calculated such that both substance 211and substance 214 are cured to an acceptable degree. The acceptabledegree of curing may be determined based on the ultimate use of sheet S.For example, it might be acceptable to cure substance 211 on the firstside of sheet S to a lesser degree in order to obtain a better curing ofsubstance 214 applied to the second side of sheet S depending on theparticular application.

[0052] Although, conditioner 215 has been described as a singleapparatus, a series of apparatus may be used to achieve the desiredcuring of the substances, if desired. For example, the series ofapparatus may be a combination of conditioners, refrigerators, wettingdevices, drying devices etc. Moreover, it may be desirable to control acombination of conditions, such as the temperature, pressure, moisturelevel, etc., inside conditioner 215 to achieve a desired result, such asa desired penetration level of sheet S by either or both of substances211 and 214.

[0053] In various embodiments, sheet S is a laminate material, such askraft paper, that is used in the manufacture of laminates, such asdecorative laminates and/or backer layers. Furthermore, although sheet Sis preferably wound in the form of a roll, for purposes of thisinvention it is not necessary that the sheet be so wound.

[0054] As noted, substance 211 may be any substance. However, in variousembodiments, substance 211 is a substance providing first desiredcharacteristics to an end product. For example, it may be desirable thata laminate material be coated with a substance to balance or counteractanother layer of the laminate. Typically, a protective layer is used toprotect the laminate from the affects of strains, such as may be causedby extreme hot, cold, and dry conditions in the environment where thelaminate is generally used. This protective layer may be coated, forexample, with a substance, such as melamine formaldehyde resin, toprovide the desired protective characteristics. However, this protectivelayer may cause warping of the laminate that may result in delaminationor even breaking of the laminate. Therefore, it may be desirable that abalancing layer be used to counteract or balance the protective layer toprevent such warping. Thus, a laminate material of various embodiments,such as kraft paper, may be coated with a substance, such as melamine,to provide the desired balancing characteristics. This coated sheet maythen be used in a backer to balance or counteract the protectivemelamine sheet, thereby eliminating the need to use a discrete melaminesheet as a balancing sheet as is done in the prior art.

[0055] Although melamine has been described above as one substanceproviding balancing, any substance that provides such a characteristicmay be used. For example, certain acrylics and polyesters may be used toprovide the desired balancing characteristics. Moreover, the scope ofthe present invention is not limited to a substance that provides abalancing characteristic, and any substance that provides first desiredcharacteristics may be used.

[0056] Similarly, substance 214 may be any substance. In variousembodiments, substance 214 is a substance providing second desirablecharacteristics in the end product. For example, in a laminate it isoften desirable that the layers of a laminate assembly be coated withphenolic resin to provide structural bonding with other laminatematerials. Thus, in the above example sheet S is coated on one side witha substance, such as melamine, providing first desired characteristicsand on the other side with a substance, such as phenolic resin,providing second desirable characteristics, and therefore, in the aboveexample, substances 211 and 214 are different substances.

[0057] Metering device 212 may be any device capable of preciselycontrolling the amount of substance 211 that remains on the first sideof sheet S. In various embodiments, metering device 212 is an air knifewhich is used to manipulate the coating on the first side of sheet S,i.e. to precisely control the amount of coating material remaining onthe surface by removing excess coating of substance 211 from the firstsurface of sheet S. Thus, in various embodiments, metering device 212comprises a sheet of air projected under pressure at an angle from aslot-shaped air nozzle onto the coated surface of sheet S. Thus, whilesheet S is supported on a moving support such as reverse roller 208, thesheet of air is projected onto sheet S so that the air strikes sheet Sat an angle such that a desired amount of substance 211 may be removedfrom sheet S.

[0058] The amount of substance 211 remaining on sheet S may be adjustedby controlling how much air is blown across the surface of sheet S, theforce of the air blown across the surface of sheet S, the angle at whichthe sheet of air strikes the surface of sheet S, and/or the time duringwhich the air knife engages the surface of sheet S, i.e. the speed atwhich the sheet is moved past the air knife and/or the time transpiringbetween the application of the coating substances and the engaging ofthe air knife. For example, by increasing the distance of meteringdevice 212 from roller 208, the amount of substance 211 remaining on thefirst side of sheet S may be increased, due to the striking force of thesheet of air against the surface of sheet S being reduced. Accordingly,various embodiments include, a set of screw adjusters which are providedat the end of metering device 212 to adjust its distance from sheet S.However, any means may be used to adjust the distance of the meteringdevice from the surface of sheet S, e.g., a pneumatic mechanicaladjuster, an eccentric and follower, an electrically powered adjustingmeans such as a computer controlled servo mechanism, etc.

[0059] Furthermore, the air pressure applied by various embodimentmetering devices 212 may be adjusted to further control the amount ofsubstance 211 that remains or that penetrates sheet S at a particularadvance speed of sheet S through the coating apparatus. For example,when a balancing (and/or protective) substance is coated on the firstside of sheet S, it is desirable that a portion of the substance stay onthe surface of sheet S and another portion of the substance penetratesheet S up to a desired level to provide the desired properties to thesheet. Thus, by controlling the air pressure applied by metering device212 to between 0.25-5 psi at an advance rate of 5-300 ft/min for sheetS, a portion of the melamine balancing substance of various embodimentsmay be maintained on the surface of the sheet, and another portion ofthe melamine balancing substance may be allowed to penetrate the sheet.

[0060] The level to which substance 211 penetrates sheet S may befurther controlled by adapting substance 211, such that a desired amountof substance 211 may penetrate through the pores present in sheet S upto a desired level. For example, by selecting solids or other particlesof different sizes to be used to form substance 211, a desired level ofpenetration of sheet S by substance 211 may be obtained. Thus, a resinsuch as a melamine formaldehyde that penetrates sheet S up to a desiredlevel may be used as substance 211. Thus, when particles of relativelysmall size are used, substance 211 may be allowed to penetrate deeperinto sheet S, than if particles of relatively large size were used.Furthermore, different solids may be used in substance 211 dependingupon the porosity of sheet S to achieve a desired penetration level ofsubstance 211 and also to prevent substance 211 from penetrating sheet Sto such a level that would prevent the desired penetration of sheet S bysubstance 214.

[0061] Moreover, as traditional kraft paper sheets are not designed toallow coating with melamine, the melamine may be treated further, ifdesired, by other substances to allow coating a kraft paper sheet withthe desired amount of melamine. For example, melamine may be treatedwith coating or wetting agents, such as ethylene glycol, cellulose,polymer acrylamides, water based thermosetting resins, and the like, toallow it to stick to the surface of kraft paper such as by changing thesurface tension of melamine or providing a carrier which is wicked bythe fibers of the kraft paper. Thus, if desired, both coating or wettingagents, and the solid particles discussed above may be used to allow adesired portion of the substance 211 to stay on the surface of sheet Sand also to allow a desired amount of substance 211 to penetrate sheet Sup to a desired level.

[0062] Metering device 216 of various embodiments illustrated in FIG. 2is in the form of a bar or rod 40 shown in FIG. 4, that drags on thesurface of sheet S. Grooves 41 may be provided on metering device 40such that when sheet S passes over rod 40, some amount of substance 214may be removed from sheet S. By changing the spacing 42 of the grooves41 on the metering device, the amount of substance 214 remaining onsheet S may be further controlled. For example, when the metering devicehas no grooves and is substantially smooth, a large amount of substance214 may be removed from sheet S. On the other hand, by providing grooveson metering device 216 and selecting their size 43 and spacing 42, theamount of substance 214 removed from sheet S may be decreased. Although,metering device 216 (of FIG. 2) described above has been discussed withrespect to a rod with grooves, any device capable of producing thedesired precise control of coating material may be used for thispurpose.

[0063] In various embodiments, it is desirable that a portion of thebalancing substance stay mostly on the surface of the kraft paper tocounteract the protective coating, a portion of which stays on thesurface of the decorative laminate to provide a scratch and abrasionresistant layer. Therefore, metering device 212 is preferably an airknife because an air knife has been found to provide far superioraccuracy as compared to other metering devices, such as the abovedescribed bar with grooves. On the other hand, it is desirable that invarious embodiments the phenolic formaldehyde resin penetrate sheet Ssuch that it impregnates sheet S up to a desired saturation level ofapproximately forty percent resin content while not saturating the sheetto a point that the second substance is contaminated, repelled, orotherwise adversely affected. Therefore, metering device 216 ispreferably a bar with grooves as the grooved bar also facilitatesimpregnating sheet S with phenolic resin up to the desired level. Itshould be appreciated that according to the present invention, the twosubstances may or may not intermix with each other depending on thedesired characteristics.

[0064] As mentioned above, the speed of the rollers or other mechanismfor controlling the throughput of sheet S may be controlled to coat thesheet with a desired amount of substances 211 and 214. In variousembodiments, the rollers rotate at 5-300 ft/min so that the desiredamounts of substances 211 and 214 may be applied to the sheet.

[0065] Furthermore, due to the application of substance 211 on the firstsurface of sheet S, sheet S might curl or otherwise be physicallyaltered before it is coated with substance 214 on the second surface.Fibers and fiber clearances on the coated side of sheet S may contractmore than those on the uncoated surface when substance 211 is applied tothe first surface. Thus, sheet S might curl with the coated surfacebeing on the inner side. Therefore, the speed of the rollers may befurther controlled in order to prevent undesired interaction of suchphysical alterations of sheet S. Metering device 216 may also beutilized to help prevent undesired interactions of these physicalalterations, such as the aforementioned curling, by controlling theamount of substance 214 that remains on the second surface of sheet S.

[0066] It is also desirable that the same amount of the balancing(and/or protective) substance be applied to the entire first surface ofsheet S to provide a uniform coating of the substance to the surface ofthe sheet. Thus, coating roller 207 has to be uniformly coated withsubstance 211, and therefore the level of substance 211 in pan 210 ispreferably precisely controlled to provide a consistent delivery ofcoating substance along a run of sheet S. In various embodiments, theamount of a balancing and/or protective substance, such as melamine,applied on the surface of sheet S is 1-20 grams per square foot and theresin content of sheet S is 14-30 percent melamine and 12-25 percentphenolic formaldehyde. However, this amount may be varied depending onthe particular application.

[0067] However, it is not desirable that the phenolic resin that isabsorbed by sheet S from the second side penetrate the first side ofsheet S. In general, the amount of the second applied substance 214absorbed by sheet S is dependent to at least a certain extent on theamount of the first applied substance 211 absorbed. Therefore, invarious embodiments, the balancing (and/or protective) substance iscoated to the surface of sheet S before the phenolic resin as at least aportion of the balancing (and/or protective) substance is controlled,according to the present invention, to remain on the surface of thesheet and, therefore, limit its interaction with the application of thesecond substance. Thus, to avoid the balancing (and/or protective)substance from being repelled by the phenolic resin, and also to achievethe desired penetration for the balancing (and/or protective) substance,in various embodiments, the balancing (and/or protective) substance isapplied to sheet S before the phenolic resin. However, it is notnecessary that the balancing (and/or protective) substance be appliedfirst, and phenolic resin may be applied before the balancing (and/orprotective) substance without departing from the scope of the presentinvention. Furthermore, if desired, in order to obtain the desiredpenetration level of the phenolic resin, the speed of the rollers may befurther controlled so that the balancing (and/or protective) substancedoes not penetrate sheet S to an extent that would repel or prevent adesired amount of penetration of sheet S by the phenolic resin.

[0068] Furthermore, the level of penetration of substances 211 and 214and the saturation level of sheet S may be controlled by controllingvarious parameters inside conditioner 215. Thus, it may be desirable todetermine a desired curing cycle for curing sheet S to obtain thenecessary saturation level of each substance. For example, in order toachieve the desired curing, sheet S may be passed through differentstages of curing so that stage one provides an optimum environment forcuring one substance, such as a substance most prone to undesiredmigration, and stage two provides an optimum environment for curing theother substance, such as a substance less likely to migrate.

[0069] In various embodiments, the ratio of the balancing (and/orprotective) substance to the phenolic resin is approximately 3:2.However, this ratio may be varied depending on the end use of thelaminate. For example, when the laminate is used as a counter top, theratio may be different than when the laminate is used as a flooringpanel or as a backer layer.

[0070]FIG. 3 shows a schematic of a sheet that has been coated on bothsides with different substances, in accordance with the presentinvention. Substance 31 is coated on one side of sheet 30 as shown sothat a portion of substance 31 remains on the surface of sheet 30 andanother portion of substance 31 penetrates sheet S up to a desired level33. Sheet 30 is coated on an opposing surface with substance 32 whichpenetrates sheet 30 up to a desired level 33 as shown. Although thedesired level of penetration of sheet S by substances 31 and 32 is shownto be almost equal, the invention is not so limited, and the desiredlevel of penetration may be varied without departing from the scope ofthe present invention. Furthermore, although substances 31 and 32 havebeen shown as distinct layers, the two substances may intermix withoutdeparting from the scope of the present invention. Furthermore, it isnot necessary that sheet 30 be fully saturated with substances 31 and 32and if desirable, portions of sheet 30 may be left unsaturated.

[0071] In order to adjust system 20 to the desired settings to enablecoating the surfaces in the proper ratio according to variousembodiments, the bone dry weight of sheet S is first determined. Oneside of sheet S is then coated with substance 211 and metering device212 and conditioner 215 adjusted until the system is capable of curingsubstance 211 to a desired level such as a desired percentage weight ofsubstance 211 as determined from a comparison of the coated weight ofsheet S and the bone dry weight of sheet S. Sheet S is then treated onlyon the second side with substance 214 and metering device 216 andconditioner 215 adjusted until the system is capable of curing substance214 to the desired ratio again as a desired percentage weight ofsubstance 214 as determined from a comparison of the coated weight ofsheet S and the bone dry weight of sheet S. Furthermore, in addition tothe metering devices and environment inside conditioner 215, thethroughput of sheet S, the amount of substances deposited initially onthe surface of sheet S and other operational conditions may be preciselycontrolled to achieve the desired result.

[0072] A monitoring device, such as a density sensor, a camera, or otheroptical sensor, or even various contact sensor devices may be providedto monitor the amount of the different substances on sheet S and also tomonitor the thickness of the sheet during manufacturing to provide asheet with the desired thickness and characteristics. This monitoringdevice preferably monitors sheet S coming out of conditioner 215periodically and provides information useful in controlling aspects ofthe coating and curing process. Furthermore, the monitoring device maybe used to monitor the dimensional stability of sheet S to ensure thatsheet S does not warp torsionally or become distorted by tensileeffects. Moreover, sheet S may be further monitored to ensure that itdoes not bulge, bend, or get deformed, as soon as it is coated on oneside.

[0073] Furthermore, system 20 may be adapted to include more than twopans and the system adjusted so that the same system may be used to coatsheet S with different substances when desired. For example, roller 203may be used to coat a different substance on sheet S and roller 217adjusted accordingly so that sheet S may be made to bypass substance211. In the alternative, if desired, only two pans may be used but adraining means provided to drain one substance from one of the pans andfill the pan with a different substance by means of a pump when a newcoating substance is to be applied.

[0074] It shall be appreciated that prior art systems do not coat akraft paper sheet with melamine resin to provide the desired balancing(and/or protective) characteristics to the laminates. Instead a resincarrier sheet is impregnated with melamine resin and used in prior artsystems to provide the desired characteristics because kraft paper sheetis not suitable for impregnation with melamine. However, the presentinvention provides for the coating of kraft paper or other laminatematerial generally not adapted for coating with melamine, by adaptingthe melamine by suspending particles of desired size in the resin tomake it suitable for impregnating the kraft paper.

[0075] Experimentation has revealed that a kraft paper sheet of thepresent invention treated with melamine resin provides improvedbalancing and protective characteristics. In performing the experiments,planks of laminate comprising a decorative laminate, a medium densityfiberboard substrate and a backer were suspended in a vertical positionin an environmentally controlled chamber. The backer in one set of suchplanks comprised of kraft paper sheet treated with melamine on one sideand phenolic resin on the other side. The backer in another set of suchplanks comprised a melamine impregnated overlay sheet of the prior art.The temperature inside the chamber was maintained at 72° F. and therelative humidity maintained at 90% from day 1 to day 7, and 10% fromday 8 to day 14. The results of the experimentation are shown in thetable of FIG. 5 and graphically represented in FIGS. 6A and 6B.

[0076] It was observed that the plank comprising of the prior art backerdemonstrated slight positive warping on day 0 because overlay paper ofthe prior art backer sheet contains fibers that absorb more moisture. Onthe other hand, the plank comprising of a backer made of kraft paperdemonstrated slight negative warping on day 0. Furthermore, the plank oflaminate material comprising of a kraft paper sheet treated withmelamine resin on one side and phenolic resin on the other sidedemonstrated lesser movement under 90% relative humidity as compared tothe plank of laminate material comprising prior art backer material.

[0077] Under 10% relative humidity, the backer sheet demonstrated morenegative movement as compared to the prior art backer sheet. However,slight negative movement of the backer is desirable to make the laminatebond more firmly with the surface on which the laminate is applied. Onthe other hand, positive movement of the backer gives the impressionthat the surface is cracked and thus, hurts the appearance of thesurface. Laminates made from prior art backer sheets tend to demonstratemore positive movement than negative movement because they use aseparate melamine impregnated overlay sheet which limits negativemovement of the laminates made from prior art backer sheets.

[0078] Thus, the various two sided coating system and method embodimentsdescribed above provide improved balancing and protective properties byprecisely controlling the amount of balancing and protective substancepenetrating sheet S and also precisely controlling the amount of thesubstance remaining on the surface of sheet S, and therefore improvingthe desired characteristics, since more of the substance is on thesurface. Moreover, the sheet providing the desired balancing andprotective characteristics is also providing the structural crosslinking due to the phenolic resin of various embodiments. Thus, betterstructural cross linking is provided as migration of phenolic resin froman adjoining sheet is not the sole source of the structural bonding ofthis sheet of the laminate assembly.

[0079] The invention as described in the various embodiments eliminatesthe need to use a discrete melamine impregnated balance sheet with alaminate to provide the desired balancing characteristics to thelaminate. Thus, substantial cost savings in terms of raw material costs,handling costs, wastage, etc. may be achieved by the present invention.

[0080] Although the present invention and its advantages have beendescribed in detail, it should be understood that various changes,substitutions and alterations can be made herein without departing fromthe spirit and scope of the invention as defined by the appended claims.Moreover, the scope of the present application is not intended to belimited to the particular embodiments of the process, machine,manufacture, composition of matter, means, methods and steps describedin the specification. As one of ordinary skill in the art will readilyappreciate from the disclosure of the present invention, processes,machines, manufacture, compositions of matter, means, methods, or steps,presently existing or later to be developed that perform substantiallythe same function or achieve substantially the same result as thecorresponding embodiments described herein may be utilized according tothe present invention. Accordingly, the appended claims are intended toinclude within their scope such processes, machines, manufacture,compositions of matter, means, methods, or steps.

What is claimed is:
 1. A method for manufacturing a laminate product,said method comprising: coating a first surface of a sheet of kraftpaper with a melamine resin, said melamine resin penetrating a firstportion of said kraft paper and enabling said coated kraft paper sheetto counteract force resulting from a sheet of laminate material to beincluded in said laminate product; coating a second surface of saidkraft paper sheet with phenolic resin, said phenolic resin penetrating asecond portion of said kraft paper sheet; forming a backer laminatecomprising said kraft paper sheet; forming a decorative laminatecomprising said sheet of laminate material; and forming said laminateproduct, said forming of said laminate product comprising: coupling saiddecorative laminate to a first surface of a substrate; and coupling saidbacker laminate to a second surface of said substrate such that saidkraft paper sheet is an outermost layer of said laminate product.
 2. Themethod of claim 1 further comprising: controlling an amount of saidmelamine resin to be applied to said first surface of said kraft papersheet based on a desired penetration level of said kraft paper sheet toallow a desired amount of said phenolic resin to be absorbed by saidkraft paper sheet.
 3. The method of claim 2 wherein said controllingcomprises: removing from said first surface of said kraft paper sheetexcess melamine resin.
 4. The method of claim 2 wherein said controllingcomprises: positioning an engagement mechanism to provide a desired biason said kraft paper sheet such that said kraft paper sheet engages afirst coating roller with a selected amount of pressure to remove excessmelamine resin.
 5. The method of claim 2 further comprising: controllingan amount of said phenolic resin to be applied to said second surface ofsaid kraft paper sheet based on a desired penetration level of saidkraft paper sheet to allow a desired amount of said melamine resin to beabsorbed by said kraft paper sheet.
 6. The method of claim 2 furthercomprising: controlling an amount of said phenolic resin to be appliedto said second surface of said kraft paper sheet to penetrate said kraftpaper sheet with a desired amount of said phenolic resin without causingundesired interaction with said melamine resin.
 7. The method of claim 6further comprising: removing from said second surface of said kraftpaper sheet excess phenolic resin to maintain a desired level ofpenetration of said kraft paper sheet by said phenolic resin and toallow a desired amount of said melamine resin to be absorbed by saidkraft paper sheet.
 8. The method of claim 7 further comprising:providing a metering device with a plurality of grooves of predeterminedspacing to remove from said second surface of said kraft paper sheetsaid amount of said excess phenolic resin.
 9. The method of claim 1further comprising: determining a ratio of said melamine resin andphenolic resin to be applied to said kraft paper to form a suitablebalancing layer of said melamine resin on said first surface and toprevent said phenolic resin from seeping through to said first surfaceof said kraft paper.
 10. The method of claim 9 wherein said ratio ofsaid melamine resin and said phenolic resin to be applied to said firstand second surfaces, respectively, of said kraft paper is approximately3:2.
 11. The method of claim 1 further comprising: determining a firstconditioning attribute for curing said melamine resin to maintain aportion of said melamine resin substantially on said first surface ofsaid kraft paper sheet and allowing a remaining portion of said melamineresin to penetrate said kraft paper sheet up to a predetermined level.12. The method of claim 11 wherein said first conditioning attribute isselected from the group consisting of: temperature; pressure; acatalyst; and moisture level.
 13. The method of claim 11 furthercomprising: determining a second conditioning attribute for curing saidphenolic resin to achieve a desired penetration level of said kraftpaper sheet.
 14. The method of claim 13 wherein said second conditioningattribute is selected from the group consisting of: temperature;pressure; a catalyst; and moisture level.
 15. The method of claim 13further comprising: curing said melamine resin by providing said firstconditioning attribute, and curing said phenolic resin by providing saidsecond conditioning attribute.
 16. The method of claim 15 wherein saidfirst and second conditioning attributes are provided by a curingdevice.
 17. The method of claim 16 wherein said curing device is atleast one device selected from the group consisting of an oven, arefrigeration device, a wetting device, and a drying device.
 18. Themethod of claim 1 further comprising: curing said kraft paper sheet; andadjusting a period said kraft paper is cured to allow proper curing ofsaid resins.
 19. The method of claim 1 further comprising: exposing saidkraft paper sheet; to a conditioning unit; controlling a rate at whichsaid kraft paper is exposed to said conditioning unit; and maintaining aconditioning attribute of said conditioning unit to prevent seepage ofsaid phenolic resin onto said first surface of said kraft paper, andmaintaining said desired amount of said melamine resin on said firstsurface of said kraft paper, penetrating a first portion of said kraftpaper, and wherein said conditioning attribute is selected from thegroup consisting of: temperature; pressure; a catalyst; and moisturelevel.
 20. The method of claim 1 wherein said first coating step furthercomprises: selecting a size of particles to be suspended in a solutionto form said melamine resin to allow said melamine resin to penetratesaid kraft paper sheet up to a desired level; and suspending particlesof selected size to form said melamine resin to achieve a desiredpenetration level of said kraft paper sheet.
 21. The method of claim 1wherein said sheet of laminate material comprises an overlay sheet. 22.The method of claim 1 wherein said decorative laminate comprises adecorative sheet.
 23. The method of claim 1 wherein said decorativelaminate comprises at least one sheet of kraft paper impregnated withphenolic resin.
 24. The method of claim 1 wherein said substratecomprises at least one material selected from the group consisting ofplywood, particle board, chipboard, and fiberboard.
 25. The method ofclaim 1 wherein said backer laminate further comprises at least oneadditional sheet of laminate material; and wherein said phenolic resinenables mechanical bonding of said kraft paper sheet to one of said atleast one addition sheets of laminate material of said backer laminate.26. The method of claim 25 wherein said at least one additional sheet oflaminate material comprises at least one kraft paper sheet.
 27. Themethod of claim 1 wherein said melamine resin is applied to said firstsurface before said phenolic resin is applied to said second surface toprevent said phenolic resin from penetrating said kraft paper beyond adesired level and to allow said melamine resin to penetrate said kraftpaper up to a desired level.
 28. The method of claim 1 wherein saidmelamine resin is melamine formaldehyde resin.
 29. A kraft paper sheetused in a laminate product, comprising: a first surface coated withmelamine resin, said melamine resin penetrating a first portion of saidkraft paper sheet and enabling said coated kraft paper sheet tocounteract force resulting from a sheet of laminate material to beincluded in said laminate product; and a second surface coated withphenolic resin, said phenolic resin penetrating a second portion of saidkraft paper sheet and providing bonding in said end product.
 30. Thekraft paper sheet of claim 30, wherein said kraft paper sheet balancesanother sheet of said laminate product.
 31. The kraft paper sheet ofclaim 30, wherein said kraft paper sheet is applied in said laminateproduct to a surface selected from the group consisting of a decorativelayer and a backer layer.
 32. The kraft paper sheet of claim 30, whereinsaid kraft paper sheet protects said end product from the affects causeddue to a strain selected from the group consisting of a thermal strain,a mechanical strain, a chemical strain, and a barometric strain.
 33. Thekraft paper sheet of claim 30, wherein a portion of said melamine resinstays substantially on said first surface of said kraft paper sheet andanother portion of said melamine resin penetrates said kraft paper sheetup to a desired level.
 34. The kraft paper sheet of claim 30, whereinsaid phenolic resin penetrates said kraft paper sheet up to a desiredlevel.
 35. The kraft paper sheet of claim 30, wherein said melamineresin is melamine formaldehyde.
 36. A sheet for use in a melamine resinprotected laminate product, said sheet comprising: a kraft paper sheet;melamine resin coating a first side of said kraft paper sheet andpenetrating a first portion of said kraft paper sheet; and phenolicresin coating an opposite side of said kraft paper sheet and penetratinga remaining portion of said kraft paper sheet, said phenolic resinadapted to migrate to cross-link with phenolic resin of another sheet ofsaid laminate product and thereby provide structural bonding into saidremaining portion of said kraft paper sheet.
 37. A laminate productcomprising: a decorative sheet; a protective coating of melamine resincoating disposed on a decorative surface of said decorative sheet; atleast one layer of phenolic resin bonding said decorative sheet to saidlaminate product; and a kraft paper balancer sheet comprising: a firstsurface coated with melamine resin, said melamine resin penetrating afirst portion of said kraft paper sheet and enabling said coated kraftpaper sheet to counteract force resulting from said melamine of saidprotective coating; and a second surface coated with phenolic resin,said phenolic resin penetrating a second portion of said kraft papersheet and providing bonding of said kraft paper sheet to said laminateproduct.